Bit of backstory.
The first three are, of course, the same lioness. All taken in relatively high sun, close to noon in the Ngorongoro Crater. She was panting, exhausted and hot in the intense sun. But there was a wildebeest carcass maybe 10-15 feet away, probably from this morning's kill. And she wasnt about to leave it.
After we watched her for5 or 10 minutes, she ambled over to the shade made by the Land Rover in front of us, cooling down. The vehicles are not perceived as a threat in general.
The last image is a different lioness, taken along the Serengeti Plains. Also around mid-day. The only food around was ours. We were about to have a picnic lunch, but found a different spot!